There are effectively three 2.4 GHz channels and about six 5 GHz channels, but because the range of 5 GHz is so much smaller you should be able to find on open 5 GHz channel even in the densest, tech heavy, apartment building.
As the author said in the comment section: "I usually suggest turning 2.4 GHz off altogether so none of your users will ever connect to it by accident."
As for AP's sharing channels, this is great in concept but our (3 unit) building became so overcrowded in the 2.4 GHz spectrum that devices couldn't connect which caused people to add more routers and repeaters to "boost" the signal making it even worse. If you can't connect, you can't share.
As the author said in the comment section: "I usually suggest turning 2.4 GHz off altogether so none of your users will ever connect to it by accident."
As for AP's sharing channels, this is great in concept but our (3 unit) building became so overcrowded in the 2.4 GHz spectrum that devices couldn't connect which caused people to add more routers and repeaters to "boost" the signal making it even worse. If you can't connect, you can't share.